ventilation cover with a light source

ABSTRACT

A cover for a fan with an outer plate ( 2 ) which is attachable to an inner plate ( 1 ) via connecting means ( 2   b ). Between the outer plate ( 2 ) and the inner plate ( 1 ) a gap ( 12 ) is provided for the passage of air between the outer plate and the inner plate. In the outer plate ( 2 ) an LED panel ( 4 ) is provided such that the LED panel ( 4 ) is electrically connected to a power supply via the connecting means ( 2   b ).

FIELD OF TECHNOLOGY

The present device relates to a cover for a fan having a light source.

BACKGROUND

In apartments or offices a ventilation unit which leads to an air duct is often installed on the ceiling or in a wall for providing forced ventilation. Typically, the ventilation unit comprises an outer box-like housing, an electrically driven fan disposed within the housing, and a grill or fan cover attached to one side of the fan housing. An air filter is often used to protect the ventilation equipment from dust. It is also common to control the operation of the fan via electronic equipment and to combine the fan with other electrical devices, such as a heater or a light source for room illumination.

SUMMARY

The application provides a cover for a fan with an outer plate. The outer plate is attachable to an inner plate via a connecting means. The cover further provides a gap for the passage of air between the outer plate and the inner plate. An LED panel is provided in the outer plate such that the LED panel is electrically connected to a power supply via the connecting means.

The application also provides a cover assembly comprising the cover for the fan and the inner plate with an air inlet, the outer plate of the cover and the inner plate being interconnected.

The LED panel which is used for illumination is thin compared with the overall thickness of the cover. This maintains the natural shape of the cover as an interior decoration and it is also an advantage over designs where the device protrudes downward from a ceiling.

The LED panel has low heat emission, therefore it will neither deform the ceiling material nor does it present a fire hazard.

The LED panel provides a uniform room illumination, not requiring further components for this purpose. However, if desired, the LED panel can be combined with other illumination sources such as light bulbs or neon tubes.

The LED panel usually has a longer life than an ordinary light bulb. Moreover, the LEDs in the LED panel can be connected in such a way that the other LEDs will continue to light if individual LEDs fail. Therefore, replacement of the LED panel is needed rarely or never during the lifetime of the ventilation unit.

The LED panel is integrated into the bottom of the cover. This design has a simple structure with only very few components. It is therefore robust and durable, especially when compared to the more complicated arrangement needed for a light bulb. No additional wires to the outer plate are required, as the LED panel is connected to a power supply via the connecting means.

The connecting means may comprise snap fits with a female part which is provided at one of the plates and with a male part which is provided at the other plate, the male part and the female part mating in a mounted state. By using snap fits, the outer plate of the cover can be easily detached for exchanging an air filter which protects the equipment in the fan housing.

The inner plate and the outer plate are maintained at a predetermined distance for providing a gap for the air inflow between the inner plate and the outer plate. This can be achieved by the weight of the outer plate against the connecting means, by the form fit of the connecting means or by protrusions on one of the plates which serve as spacers.

The snap fits may be formed for maintaining the inner plate and the outer plate at a predetermined distance. They leave a gap for the passage of air between the inner plate and the outer plate.

The female part of the snap fit may comprise two or more resilient arms. The male part of the snap fit may comprise a base portion and a top portion. The width of the top portion is greater than the width of the base portion. The resilient arms of the female part are formed so as to enclose the top portion of the male part in an attached state.

The male part of the snap fit can also comprise a plug. The plug has resilient arms with protruding ends. The female part may comprise an opening, such that the resilient arms are locked into the opening by the form fit of the protruding ends.

A further type of snap fit has a pin with one or more grooves on its surface as male part and a female part with two or more resilient arms which fit into the grooves of the male part.

In a further embodiment, the connecting means comprises a hinge with an upper arm and a lower arm and an opening in the outer plate which takes up the hinge. The upper arm of the hinge is connected to the inner plate and the lower arm of the hinge is connected to the lower end of the upper arm by a joint, such that the lower arm can be rotated about a horizontal axis. The hinge also has a mechanism to fix the lower arm at a predetermined angle relative to the upper arm.

The connecting means may also be made up of a threaded bolt which is attached to the inner plate, an opening in the outer plate for receiving the bolt and a nut on the thread of the bolt.

In another embodiment the connecting means comprise a plug with protruding ends which is connected to one of the plates. Rotatable angles are provided on the other plate on the opposite side. The protruding ends of the plug fit into the space between the rotatable angles and the plate on which the angles are provided.

One way of assembling the LED panel into the outer plate is to integrate the LED panel into the center of the outer plate.

The term ‘ventilation unit’ refers to a fan housing with all parts contained in the housing, together with the aforementioned cover assembly.

The ventilation unit or the cover assembly may be connected with two power supply terminals, one terminal for the LED panel and one terminal for the fan. Then the fan and the LED can be switched on and off independently.

A timer may switch off the fan a fixed time after the LED panel has been switched off.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 illustrates an illuminating cover attached to a fan housing,

FIG. 2 illustrates a perspective bottom view of the illuminating cover of FIG. 1,

FIG. 3 illustrates an interior view of the illuminating cover of FIG. 1,

FIG. 4 illustrates a side view of the illuminating cover of FIG. 1,

FIG. 5 illustrates an exploded perspective view of a further illuminating cover with the fan housing of FIG. 1,

FIG. 6 illustrates a means of connecting an inner plate to an outer plate of a further embodiment,

FIG. 7 illustrates a second means of connecting an inner plate to an outer plate of a further embodiment,

FIG. 8 illustrates a third means of connecting an inner plate to an outer plate of a further embodiment,

FIG. 9 illustrates a fourth means of connecting an inner plate to an outer plate of a further embodiment,

FIG. 10 illustrates a fifth means of connecting an inner plate to an outer plate of a further embodiment, and

FIG. 11 illustrates a sixth means of connecting an inner plate to an outer plate of a further embodiment.

DETAILED DESCRIPTION

In the following description, details are provided describing the embodiments of the application. It shall be apparent to one skilled in the art, however, that the shown embodiments may be practised without such details.

FIG. 1 shows a ventilation unit 13 with a cover 3 which is attached to a fan housing 10. The horizontal extension of the cover 3 is larger than the bottom area of the fan housing 10. Therefore, when in an installed state, the cover 3 is hiding the fan housing 10.

The cover 3 comprises an inner plate 1 and an outer plate 2. An LED panel 4 is fitted into the center portion of the outer plate 2. The LED panel 4 is made up of a plurality of interconnected LEDs and it comprises two contacts for the connection of a power source. Arrows 6 indicate radiated light from the LED panel 4. The outer plate 2 is attached to the inner plate 1 such that there is a gap 12 left between the inner plate 1 and the outer plate 2. The gap 12 can be best seen in FIG. 4.

The fan housing 10 contains a fan which is not shown in the figures. Electronic control modules and lead wires required for the operation of both the fan and the LED panel 4 form part of the ventilation unit 13 but are also not shown in the figures. At one side of the fan housing 10 an exhaust tube 11 is provided, as can be seen in FIG. 1. The fan generates an airflow through the cover 3 and the fan housing 10 to the exhaust tube 11 the airflow being indicated by arrows. Arrows 5 indicate the air inflow through the gap 12 between the inner plate 1 and the outer plate 2. Arrow 105 shows the air outflow through the exhaust tube 11 of the fan housing 10.

FIG. 2 is a bottom view of the cover 3, showing the outer plate 2, with LED panel 4 in greater detail. FIG. 2 further shows side faces of the inner plate 1 and the gap 12 between the inner plate 1 and the outer plate 2.

FIG. 3 is a perspective top view of the cover 3 illustrating details of the inner plate 1. FIG. 3 also shows part of the side face of the outer plate 2. The inner plate 1 comprises an air inlet 1 a. Inside the air inlet 1 a there is provided a mesh shaped grill 1 b. A filter plate which is not shown in FIG. 3 is provided below the mesh shaped grill 1 a. Pins 2 b serve to fix the outer plate 2 to the inner plate 1. FIG. 3 shows only the ends of the pins 2 b protruding from the inner plate 1. The electrical connection between the pins 2 b and the LED panel 4 is realized in the following way which is not shown in the figures. An electronic rectifier which is included in the ventilation unit 13 converts the alternating input current of the fan into a direct current. A lead wire connects the positive output of the rectifier to one of the pins 2 b and a second lead wire connects this pin to a contact of the LED panel 4. In the same way another pin 2 b connects the negative output of the rectifier to the other contact of the LED panel 4.

FIG. 4 shows a side view of the cover 3. One of the curved side faces of the cover 3 and also part of the bottom of the cover 3 are shown in this figure. FIG. 4 also illustrates part of the mesh shaped grill 1 b which is formed in the air inlet 1 a of the inner plate 1 as can be best seen in FIG. 3. The gap 12 between the two plates as well as the location of the pins 2 b can be seen in this perspective. FIG. 4 shows also part of the LED cover 4 which is built into the outer plate 2.

The LED panel which is used for illumination is thin compared with the thickness of the cover. This maintains the natural shape of the cover as an interior decoration and it is also an advantage over designs where the device protrudes downward from a ceiling.

The LED panel has low heat emission, therefore it will neither deform the ceiling material nor does it present a fire hazard.

The LED panel provides a uniform room illumination, not requiring further components for this purpose. However, if desired, the LED panel can be combined with other illumination sources such as light bulbs or neon tubes.

The LED panel usually has a longer life than an ordinary light bulb. Moreover, the LEDs in the LED panel can be connected in such a way that the other LEDs will continue to light if individual LEDs fail. Therefore, replacement of the LED panel is needed rarely or never during the lifetime of the ventilation unit.

The LED panel is integrated into the bottom of the cover. This design has a simple structure with only very few components. It is therefore robust and durable, especially when compared to the more complicated arrangement needed for a light bulb. No additional wires to the outer plate are required, as the LED panel is connected to a power supply via the connecting means.

The inner plate 1 and the outer plate 2 may be formed in a different shape from that shown in the description. For example, the surface may be flat rather than curved.

Various fan types, such Axial fans, centrifugal multiblade fans or cross flow fans—among other types—can be used.

There may be other ways of controlling the illumination and the fan. For example, the LED panel and the fan may be switched on and off separately. In that case, a separate control cable for switching the LED panel 4 is connected to the ventilation unit 13.

The fan may also be operated by an electronic control. A timer may switch off the fan a fixed time after the light has been switched off.

In an installed state, the ventilation unit 13 is connected to a power cable in a wall, the power cable having a switch to close the electric circuit. Once the user operates the switch, the device becomes connected to an alternating current supply and electrical power drives the fan. An electronic rectifier included in the ventilation unit 13 converts the alternating current into a direct current which provides a suitable power supply for the LED panel 4. The direct current flows over one of the connecting pins 2 b to the LED panel 4 and back over another pin 2 b. The LED panel 4 then gives off light to illuminate the room. An operation in which the LEDs in the LED panel 4 provide rectification of the AC power is possible, too.

For installing the ventilation unit 13, the fan housing 10 is integrated into a wall or into the ceiling of a room. The exhaust tube 11 of the fan housing 10 is connected to a ventilation pipe in the wall and the lead wire to the fan is connected to a power cable in the wall. Then the outer plate 2 is connected to the inner plate 1. The cover 3 is then fixed to the fan housing 10 by attaching the inner plate 1 to the fan housing 10. In the installed state the fan housing 10 is located inside the ceiling or wall and the cover 3 faces to the interior of the room concealing the fan housing 10.

Typically the device is operated by using a wall switch that controls the electrical power to the fan.

FIG. 5 shows an exploded view of a ventilation unit 113. The ventilation unit 113 is similar to the ventilation unit 13 of FIGS. 1-4. Similar parts have the same reference numbers. The outer plate 102 and the inner plate 101 are connected by a snap fit 19. The snap fit 19 comprises a female part 20 and a male part 21. The female part 20 of the snap fit 19 is attached to the inner plate 101. The male part 21 of the snap fit 19 is attached to the outer plate 102. This type of snap fit is shown in greater detail in the cross section drawing of FIG. 6.

The male part 21 of the snap fit 19 comprises a base portion in the form of an elongated plate 22 and a top portion 23 on the upper edge of the plate, the top portion having the form of an elongated cylinder.

The female part 20 of the snap fit 19 is a type of clip which comprises two resilient arms. The resilient arms are symmetrical to a center line and formed to match the male part. Each of the resilient arms comprises a base portion in form of an elongated plate, a middle portion in form of a half tube and a top portion in form of an angled elongated plate. The half tube is located at the upper edge of the elongated plate. The angled elongated plate is located at the upper edge of the half tube and is bent away from the centre line to guide the male part 21 when it is inserted into the female part 20. In the connected state shown in FIG. 6 the resilient arms of the female parts 20 enclose the male parts 21.

Lead wires in the outer plate 102 which are not shown in FIG. 6 connect the contacts of the LED panel 4 to the male part 21. The female parts 20 are connected to the respective plus- and minus poles of the direct current supply in the way mentioned in embodiment 1.

The male part 21 and the female parts 20 form one possible type of snap fits.

In the installed state the resilient arms of the female parts 20 enclose the male part 21. By the inward force of the female parts 20 the male part 21 is held in position.

When direct current is supplied in the way described for embodiment 1 the current flows from the female parts 20 over the male part 21 and the lead wire to the LED panel 4. The current flows back to the minus pole over a second lead wire, a second male part 21 and attached female parts 20.

The fan housing 10 is assembled as described in embodiment 1. Then the outer plate 102 is attached to the inner plate 101 with the parts shown in FIG. 6. To attach the outer plate 102 to the inner plate 101 the male part 21 is inserted into the resilient arms 20.

FIG. 7 illustrates a second means of connecting the inner plate 201 to the outer plate 202. The second means of connecting comprises a plug 27. The plug 27 is connected to the inner plate 201 and includes resilient arms 29 with protruding ends. Formed in the outer plate 202 is a hole 28 with bulges at the end of the hole 28. The plug 27 fits into the hole 28 of the outer plate 202 and the protruding ends of the resilient arms fit into the corresponding bulges at the end of the hole 28.

Lead wires in the outer plate 202 which are not shown in FIG. 7 connect the contacts of the LED panel 4 to contacts in the outer plate 202 which are not shown in FIG. 7. The contacts in the outer plate 202 are in mechanical contact with the plugs 27. The plugs 27 are connected to the respective plus- and minus poles of the current supply in the way mentioned in embodiment 1.

The plug 27 and the corresponding hole in the outer plate 202 form one possible type of snap fit.

The resilient arms 29 exert an outwardly directed force on the hole 28. This force keeps the arms 29 secured against the hole 28 because the arms 29 have to bend outwards against this force for the protruding ends to move out of the bulges and slide back through the hole 28.

When direct current is supplied in the way described for embodiment 1 the current flows over the plug 27, a contact inside the hole 28 and a lead wire to the LED panel 4. The current flows back to the minus pole over a second lead wire, a second contact and a second plug 27.

The fan housing 10 is assembled as described in embodiment 1. Then the outer plate 202 is attached to the inner plate 201 with the parts shown in FIG. 7. To fix the outer plate 202 to the inner plate 201 the plug 27 is inserted into the hole 28 of the outer plate 202. When the plug 27 is inserted into the hole 28 the resilient arms 29 are pressed toward each other. Then the plug 27 is moved to the end of the hole 28 until the protruding ends of the resilient arms 29 move outwards into the corresponding bulges at the end of the hole 28.

FIG. 8 illustrates a third means of connecting the inner plate 301 to the outer plate 302. The means comprises a pin 32 fixed to the inner plate 301 and two resilient arms 33 which form part of the outer plate 302. The pin 32 comprises two grooves on its surface. The two resilient arms 33 comprise a protrusion on the inner side of their ends. In the assembled state shown in FIG. 8 the protrusions at the end of the resilient arms 33 fit into the corresponding grooves on the surface of the pin 32.

Lead wires in the outer plate 302 which are not shown in FIG. 8 connect the contacts of the LED panel 4 to at least one of the resilient arms 33. The pins 32 are connected to the respective plus- and minus poles of the current supply in the way mentioned in embodiment 1.

The pin 32 and the two resilient arms 33 form one possible type of snap fits.

The snap fits described in embodiment 2-4 also serve to maintain the plates at a fixed distance, thereby leaving a gap for the passage of air between the plates 101, 102; 201, 202; 301, 302.

The pin 32 may have different shapes. For example the pin 32 may have the shape of a plate and the grooves may be formed on both sides of the plate. Or the pin 32 may be cylindrically shaped and the groove may be formed on the perimeter of the cylinder.

The arms 33 exert an inwardly directed force onto the grooves on the surface of the pin 32. This force keeps the plates connected because the arms 33 have to bend outwards against this force for the protrusions to move out of the grooves.

When direct current is supplied in the way described for embodiment 1 the current flows over the pin 32, the arms 33 and a lead wire to the LED panel 4. The current flows back to the minus pole over a second lead wire, arms 33 and a second pin 32.

The fan housing 10 is assembled as described in embodiment 1. Then the outer plate 302 is attached to the inner plate 301 with the parts shown in FIG. 8. To fix the outer plate 302 to the inner plate 301 the pin 32 is inserted into the arms 33. When the pin 32 is inserted the arms 33 on the outer plate 302 bend outwards and remain bent until the protrusions of the arms 33 fit into the grooves on the surface of the pin 32.

FIG. 9 illustrates a fourth means of connecting the inner plate 401 to the outer plate 402. The fourth means of connecting includes a hinge. The hinge comprises an upper arm 35 and a lower arm 36. The upper arm is connected to the inner plate 401. The lower arm 36 is connected to the lower end of the fixed arm 35 by a joint such that the lower arm 36 can be rotated about a horizontal axis.

In the open position both arms are in a straight line. In the closed position the lower arm forms a right angle with the upper arm. The hinge comprises a mechanism to fix the lower arm 36 at a certain angle in the closed position, such as a spring and groove mechanism, which is not shown in FIG. 9.

Formed in the outer plate 402 is a hole 37 and a hollow at the bottom of the outer plate 402 that takes up the lower arm in a closed position.

Lead wires in the outer plate 402 which are not shown in FIG. 9 connect the contacts of the LED panel 4 to a contact in the outer plate 402, the contact being in mechanical contact with the hinge. The contact in the outer plate 402 is not shown in FIG. 9. The hinges are connected to the respective plus- and minus poles of the current supply in the way mentioned in embodiment 1.

The lower arm 36 is locked in the closed position by the fixing mechanism. Thereby it takes up the weight of the lower plate 402.

When direct current is supplied in the way described for embodiment 1 the current flows over the hinge and a contact in the outer plate 402 to the LED panel 4. The current flows back to the minus pole over a second lead wire, a second contact and a second hinge.

The fan housing 10 is assembled as described in embodiment 1. Then the outer plate 402 is attached to the inner plate 401 with the hinge shown in FIG. 9. To fix the outer plate 402 to the inner plate 401 the hinge is inserted into the hollow 37 of the outer plate 402 in the open position. Then the lower arm 36 is rotated until is snaps into the closed position and the hollow in the outer plate 402 takes up the lower arm 36. In the closed position the lower arm 36 is at a right angle with the upper arm 35.

FIG. 10 shows a fifth means of connecting the inner plate 501 to the outer plate 502 comprising a nut 41 and a threaded bolt 40. The bolt 40 is attached to the inner plate 501. Formed in the outer plate 502 is a hole positioned to accept the bolt 40.

A contact in the hole and a lead wire which are not shown in FIG. 10 connect the contacts of the LED panel 4 to the bolt 40. The two bolts 40 are connected to the respective plus- and minus poles of the direct current supply in the way mentioned in embodiment 1.

In the embodiments 5 and 6 the inner and the outer plate are maintained at a fixed distance, thereby leaving a gap for the passage of air between the inner and the outer plate. This can be achieved by the weight of the outer plate alone or by protrusions on one or both of the plates.

In order to hide the nut 41, the hole in the outer plate 502 may be wider at its outer side to take up the nut 41. Instead of the nut 41 a screw cap or an Allenhead screw may be used.

The bolt 40 cannot slide back through the hole in the outer plate 502 when the nut 41 is fastened to the bolt 40 as the diameter of the nut 41 is larger than the diameter of the hole. Therefore the weight of the outer plate 502 keeps the outer plate 502 fixed to the inner plate 501.

When direct current is supplied in the way described for embodiment 1 the current flows over the bolt 40, a contact inside the hole in the outer plate 502 and a lead wire to the LED panel 4. The current flows back to the minus pole over a second lead wire, a second contact and a second bolt 40.

The fan housing 10 is assembled as described in embodiment 1. Then the outer plate 502 is attached to the inner plate 501 in the following way. The bolt 41 is inserted into the hole of the outer plate 502. Then the nut 41 is screwed on the bolt 40 from the outer side of the outer plate 502.

FIG. 11 shows a sixth means of connecting the inner plate 601 to the outer plate 602. The sixth means comprises a plug 43 which is connected to the inner plate 601 and rotatable angles 44 which are connected to the outer plate 602. The plug 43 comprises protrusions 45 at its end. The plug 43 with the protrusions 45 has got a T-shaped profile. The angles 44 can be rotated around a vertical axis. In a closed position as shown in FIG. 11 the angles 44 are pointing inwards and the protruding ends 45 of plug 43 fit into the space between the angles 44 and the outer plate 602.

Lead wires in the outer plate 602 which are not shown in FIG. 11 connect the contacts of the LED panel 4 to at least one of the angles 44 in the outer plate 602. The plugs 43 are connected to the respective plus- and minus poles of the current supply in the way mentioned in embodiment 1.

The plates 601, 602 are maintained at a fixed distance, thereby leaving a gap for the passage of air between the plates. This is achieved by the plug 43 which serves as separator piece.

When the angles 44 are in closed position they are pressed against the protruding ends 45 of the plug 43 preventing the plug 43 from sliding off.

When direct current is supplied in the way described for embodiment 1, the current flows over the plug 43, the angles 44 and a lead wire to the LED panel 4. The current flows back to the minus pole over a second lead wire, second angles 44, and a second plug 43.

The fan housing 10 is assembled as described in embodiment 1. Then the outer plate 602 is attached to the inner plate 601 with the plug 43 shown in FIG. 11. The angles 44 are rotated such that their ends point outwards. Then the plug 43 is inserted between the two angles 44 so that the end of plug 43 is in contact with the outer plate 602. To secure the plug 43 in this position the angles 44 are rotated back such that the ends of the angles 44 point inwards.

REFERENCE NUMBERS

-   -   1 inner plate     -   1 a air inlet 1 b mesh shaped grill 1 c curved surface of inner         plate     -   2 outer plate     -   2 a bottom of outer plate     -   2 b connecting means     -   2 c curved surface of outer plate     -   3 cover     -   4 LED panel     -   5 air inflow     -   6 radiated light     -   10 fan housing     -   11 exhaust tube     -   12 gap between inner and outer plate     -   13 ventilation unit     -   20 female part of snap fit in FIGS. 5,6     -   21 male part of snap fit in FIGS. 5,6     -   22 bottom portion of part 21     -   23 top portion of part 21     -   27 plug     -   28 groove in plug 27     -   29 protruding ends of resilient arms     -   32 pin     -   33 resilient arms     -   35 fixed arm     -   36 rotatable arm     -   37 hollow     -   40 threaded bolt     -   41 nut     -   43 part with protruding ends     -   44 rotatable angle     -   101 inner plate in embodiment 2     -   102 outer plate in embodiment 2     -   105 air outflow     -   113 ventilation unit in embodiment 2     -   201 inner plate in embodiment 3     -   202 outer plate in embodiment 3     -   301 inner plate in embodiment 4     -   302 outer plate in embodiment 4     -   401 inner plate in embodiment 5     -   402 outer plate in embodiment 5     -   501 inner plate in embodiment 6     -   502 outer plate in embodiment 6     -   601 inner plate in embodiment 7     -   602 outer plate in embodiment 7 

1. A cover for a ventilation device, comprising an outer plate (2), the outer plate (2) being attachable to an inner plate (1) via connecting means (2 b), the cover further providing a gap (12) for the passage of air between the outer plate (2) and the inner plate (1), wherein an LED panel (4) is provided in the outer plate (2) such that the LED panel (4) is electrically connected to a power supply via the connecting means (2 b). A cover assembly comprising the cover according to claim 1 and an inner plate (1) with an air inlet (la). The cover assembly (3) according to claim 2, characterized in that the connecting means comprise snap fits with a female part (20; 28; 33) which is provided at one of the plates (101, 102; 201, 202; 301, 302) and with a male part (21; 27; 32) which is provided at the other one of the plates (101, 102; 201, 202; 301, 302), the male part (21; 27; 32) and the female part (20; 28; 33) mating in a mounted state. The cover assembly (3) according to claim 3, characterized in that the snap fits maintain the inner plate (101; 201; 301) and the outer plate (102; 202; 302) at a predetermined distance, thereby leaving a gap (12) for the passage of air between the inner plate (101; 201; 301) and the outer plate (102; 202; 302). The cover assembly (3) according to claim 3 or claim 4, characterized in that the female part (20) comprises at least two resilient arms and the male part (21) comprises a base portion (22) and a top portion (23), the width of the top portion (23) being greater than the width of the base portion (22) and the resilient arms being formed to enclose the top portion (23) of the male part (21) in an attached state. The cover assembly (3) according to claim 3 or claim 4, characterized in that the male part comprises a plug (27) having resilient arms with protruding ends (29), and the female part comprises an opening (28), such that the resilient arms are locked in the opening (28) by the form fit of the protruding ends (29). The cover assembly (3) according to claim 3 or claim 4, characterized in that the male part comprises a pin (32) with one or more grooves on its surface, and the female part comprises two or more resilient arms (33) which fit into the grooves of the male part (32). The cover assembly (3) according to claim 2, characterized in that the connecting means comprises a hinge with an upper arm (35) and a lower arm (36), an opening in the outer plate (402) which takes up the hinge, the upper arm (35) being connected to the inner plate (401), the lower arm (36) being connected to the lower end of the upper arm (35) by a joint such that the lower arm (36) can be rotated about a horizontal axis, and the hinge having a mechanism to fix the lower arm (36) at a predetermined angle relative to the upper arm (35). The cover assembly (3) according to claim 2, characterized in that the connecting means comprises a threaded bolt (40) being attached to the inner plate (501), an opening in the outer plate (502) for receiving the bolt (40) and a nut on the thread of the bolt (40). The cover assembly (3) according to claim 2, characterized in that the connecting means comprises a plug (43) with protruding ends (45) which is connected to one of the plates (601,602), and rotatable angles (44) which are provided at the other one of the plates (601, 602), the protruding ends (45) of the plug (43) fitting into the space between the rotatable angles (44) and the plate on which the angles are provided. The cover assembly (3) according to one of the aforementioned claims, characterized in that the LED panel (4) is provided in an integral form in the center of the outer plate (2; 102; 202; 302; 402; 502; 602). The cover assembly (3) according to one of the aforementioned claims, characterized in that the cover assembly is connected with two power supply terminals, one terminal for the LED panel (4) and one terminal for the fan. The cover assembly (3) according to one of the aforementioned claims, characterized in that a timer switches off the fan a fixed time after the LED panel (4) has been switched off. A ventilation unit with a cover assembly (3) according to one of the aforementioned claims. 